Creating a form-fitting "Cocoon" for a knife or Multi-Tool...

[neillcurrie]

I made this blog post which details how I make a lightweight, wear-reducing, form-fitting, pocket-lint-restricting "Cocoon". I use them mostly on Vic and Wenger SAK's, and smaller multi-tools like the Leatherman PS4.
http://blogericious.blogs...ing-cocoon-for-knife.html

Creating a form-fitting "Cocoon" for a knife or Multi-Tool...   

The advantages of keeping your knife or Multi-Tool inside a custom made "Cocoon" are many. It keeps the item from accumulating pocket lint. It stops bangs and dents from marring the tool, which is an inevitable result of general pocket carrying. It quietens things down in your pocket somewhat as the Cocoon adds sound-deadening qualities. And it prevents wear to any other items that share the same pocket. A Cocoon adds very little thickness or bulk, and the tool or knife can be extracted from its Cocoon very quickly indeed. To my mind, there are so many advantages that I make a Cocoon for every knife or tool that I carry frequently. Here's how to make one. Take the tool/knife, and try slipping it inside Electrical shrink-tubing. It needs to slide in, without undue force, and not be a really sloppy fit. Shrink-tubing is available cheaply in a huge variety of diameters, usually sold by the foot, on Ebay. For my Vic Compact here, I found that 20mm diameter tubing was perfect. Cut the tubing about 1/4 inch longer than the knife. The extra will form around the ends of the knife after molding, increasing retention, and reducing wear and tear on the very ends of the tool. Take some Priority Mail tape, and wrap 2 thicknesses around the whole knife. Smooth it out as best you can.


 Look at the tool/knife in profile, and imagine trying to extract it from a form-fitting tube. You'll want the greater volume to be at the end that you mold first. I have found that all my Victorinox knives extract easiest by pulling on their keyring attachments, so I always make my Cocoons with the keyring on what will end up being the open end of the Cocoon, with the keyring at the bottom. Slide the tool/knife into the tubing after rubbing a little light oil on to the Priority Mail tape. Without the oil, you will have a very hard time extracting the knife/tool.



 Now, I use a cigarette lighter, with a medium to low flame for this next part. I guess a Heat Gun would be best, but I don't have one. A lighter allows for a more precise heat application anyway. I apply heat to the tubing, not too close, not too far, constantly moving the flame, till the tubing contracts tightly around just the "tight half" of the knife/tool (the end of the tool that you envision extracting it by). Don't do more than half of the length.



 Stop heating the tube, let it cool a minute or two, then, using a toothbrush end, or a small dowel, push out the knife tool. Remembering the orientation of the tube to the knife/tool, cut a small slit, with a rounded end (otherwise the tube may tear with use). This slit will permit the tube to give enough, and you'll be able to get the knife/tool in/out easily soon.



 Return the knife/tool to the tube, in the correct orientation, and repeat the heating process to shrink down the whole tube till it fits seamlessly, and without lose areas.



 Next, pull out the knife/tool through the slit you made. It should slide out reasonably easily. Remember, it still has the Priority Mail Tape on it, when you remove this, it'll slide easier still. Remove the Tape, and the Cocoon and knife/tool will look like this.



 Finally, carefully trim the Cocoon around its opening for neatness, and check for fit as you slide the knife/tool in several times. I find that making small changes slowly is best. You can never add material back on !! Also, the best scissors to use are the tiny scissors on Vic Classic's, Rambler's, MiniChamp's etc. Tight circular cuts are best made in an anti-clockwise direction. Lastly, the area that often gets caught up with Victorinox knives, is the area around the corkscrew (if your knife has one). The most central first wind of the corkscrew catches easily on the thin shrink-tubing, and I usually pare back the tubing in this area till the corkscrew clears easily. Remove the oil on the inside of the tubing with a cloth, and check for final fit. You have something that probably looks like this:



 If you still have issues with the Cocoon being too tight a fit, you can try paring away a little more on the areas that might be catching, or I have also used a very small amount of Baby Powder rubbed in to the inside of the Cocoon. Conversely, if the fit should be too lose for you, put the knife into the Cocoon (without the Priority Mail tape on it), and gently warm an area of the tubing till you see it start to contract a little more. Keep checking for tightness, Don't overdo this part. If you want to hide the lettering that runs the length of the Cocoon, you can use a black Sharpie, or sometimes the lettering will easily buff off with a little metal polish.

[ducttapetech]

That is cool.

sent from Ducttapetech's mobile device

[comis]

Thank you!  I will try that soon!

[Xavsbud]

This is sweet. It is so happening. I have a bunch of pocket tools that will get these if I can make it looks as nice of yours.

Dave

[NG VI]

I can't wait to try this out!

[Steinar]

Nice! 

[enki_ck]

Thanks for doing this as promised. It would maybe be better though if we had a copy of that blog post here too so as long as MTO is here, the tutorial would be here too.

[neillcurrie]

Well, it's easy to send you the text portion.
Problem is, all the pics: multitool.org won't/doesn't allow me to store them there, so I would have to upload them to a host (google pics) and then link to them individually. It's still dependent upon me keeping the pics at google for ever, otherwise the links will go bad.
This whole rigamarole is why I did it as a blog entry, and just linked to that. I'm asking for multitool.org to be more flexible, and allow pics to be hosted "on site". But maybe multitool.org has a reason for making things more difficult??
That said, I can send you the text and all the pics, and you could do whatever's necessary with them.

[frjack]

Great job! Thanks for that.

I guess even a hamfisted pillock like me could make a good attempt at that.

[Zed]

Well ive loads of old inner tubes in my shed so im going to give this a go 

[frjack]

Well ive loads of old inner tubes in my shed so im going to give this a go 

Won't work. You need electrical heat-shrink tubing. Your inner tubes will either melt or burn. 

[enki_ck]

Well, it's easy to send you the text portion.
Problem is, all the pics: multitool.org won't/doesn't allow me to store them there, so I would have to upload them to a host (google pics) and then link to them individually. It's still dependent upon me keeping the pics at google for ever, otherwise the links will go bad.
This whole rigamarole is why I did it as a blog entry, and just linked to that. I'm asking for multitool.org to be more flexible, and allow pics to be hosted "on site". But maybe multitool.org has a reason for making things more difficult??
That said, I can send you the text and all the pics, and you could do whatever's necessary with them.

Check the original post. Hope it's OK.

MTO does in fact allow you to host images, documents, ... in every post you make. Click the + Attachments and other options and you can attach up to 4 photos per post (if you require more pics, you can add a second post ).  They will be at the bottom of the post but you can use the [ img ] code to place them inside the text. We also have galleries on both the wikis (SAK and multitool) anyone can use and link pics from and a resident gallery.multitool.org. There was some talk about using the gallery.multitool.org as an alternative to all the photo hosting services but some technical difficulties (multi user friendly) are preventing us at that at the moment.

[neillcurrie]

Well, it's easy to send you the text portion.
Problem is, all the pics: multitool.org won't/doesn't allow me to store them there, so I would have to upload them to a host (google pics) and then link to them individually. It's still dependent upon me keeping the pics at google for ever, otherwise the links will go bad.
This whole rigamarole is why I did it as a blog entry, and just linked to that. I'm asking for multitool.org to be more flexible, and allow pics to be hosted "on site". But maybe multitool.org has a reason for making things more difficult??
That said, I can send you the text and all the pics, and you could do whatever's necessary with them.

Check the original post. Hope it's OK.

MTO does in fact allow you to host images, documents, ... in every post you make. Click the + Attachments and other options and you can attach up to 4 photos per post (if you require more pics, you can add a second post ).  They will be at the bottom of the post but you can use the [ img ] code to place them inside the text. We also have galleries on both the wikis (SAK and multitool) anyone can use and link pics from and a resident gallery.multitool.org. There was some talk about using the gallery.multitool.org as an alternative to all the photo hosting services but some technical difficulties (multi user friendly) are preventing us at that at the moment.

Good to know, that ability had totally escaped me and I thought I had looked hard for it.
The original post looks fine..........now 

[enki_ck]

Glad you like it. And thanks again for the write up and pics. I'll be trying it out as soon as I get some bigger sized tubing.

[neillcurrie]

Glad you like it. And thanks again for the write up and pics. I'll be trying it out as soon as I get some bigger sized tubing.

As I mentioned, Ebay has a great selection. I generally use the keywords "shrink tubing", and the size in mm, then chose the "search by" function, lowest price first.
It depends upon the size I am looking for, but 20mm diameter is a good fit for 1 or 2-layer SAK's, and I also have 22mm and 25mm.
25mm will probably accommodate a 4 layer SAK.
Amazon has a lot of the tubing too.

[pfrsantos]

Very nice tutorial, thanks.

I have a few questions:

Is it possible to show a picture of the "end" of the cocoon, the part opposite the end from which we pull out the knife? I'm guessing it has a round hole to avoid vacuum and that it is made just by shrinking the tube. Am I right?

If we wrap the knife in that kind of transparent film used for wraping food, does it work or will it "melt" along with the tube? The tape you mention doesn't leave glue residues in the knife?

Thanks again!
 

[pfrsantos]

Just got 50cm of tube to try my hand at creating some protective cocoons for a few of my Vics.

I had my Sportsman with me and the 25mm diameter tubing was the best fit. 20mm diameter tubing couldn't pass over the corkscrew. The guy at the store told me this tube shrinks up to about 50% so I guess it will turn out fine. I'll try to use it in the Climber, too.

[neillcurrie]

Very nice tutorial, thanks.

I have a few questions:

Is it possible to show a picture of the "end" of the cocoon, the part opposite the end from which we pull out the knife? I'm guessing it has a round hole to avoid vacuum and that it is made just by shrinking the tube. Am I right?

If we wrap the knife in that kind of transparent film used for wraping food, does it work or will it "melt" along with the tube? The tape you mention doesn't leave glue residues in the knife?

Thanks again!
 

Here's a pic of several Cocoons. From left to right: Vic Compact, Vic Climber, Leatherman P4 and Vic 8-blade Minichamp (with flashlight and pen scales). There's also a Pico e-Gear flashlight and a Plackers toothpick and Vic Tweezers shrunk in Cocoons to the keyring.
Correct, there's a circular end open, the extra length of the tubing shrinks down to form it. If you cut the tubing too long this end will just look weird. If too short, then the knife might be able to move down the Cocoon too much. 0.25 inches extra, split between the two ends, seems to be the perfect sweet spot.
The Priority Mail tape is the best option to use. It leaves no residue (of note) afterwards, and is strong enough to smooth out the knife bumps well. It's also free 
You can use almost any type of tape though: the temperatures never get so high that the tape would melt. I chose Priority Mail tape as it is a uniform thickness across the USA, and thus provides the correct amount of gap between the knife and the Cocoon......otherwise the fit will have to be fine tuned if you use another/different tape with a different thickness. That's why I said the tape I use, and that I use exactly 2 thicknesses of it.
All the Shrink-Tubing I have read the specifications for has stated that the tubing shrinks about 50% in diameter, 0% in length. I can pretty much verify the length shrinkage percentage, but I've never measured the diameter shrinkage percentage, but 50% seems like a decent guess. Seems like whatever brand tubing you use you'll be OK, as long as you make the length plus 0.25 inches, and chose the diameter such that the taped knife/tool will just slide inside. I have several different brands, in many different diameters, and provided I've stuck to the guidelines have always had success.

[neillcurrie]

Just got 50cm of tube to try my hand at creating some protective cocoons for a few of my Vics.

I had my Sportsman with me and the 25mm diameter tubing was the best fit. 20mm diameter tubing couldn't pass over the corkscrew. The guy at the store told me this tube shrinks up to about 50% so I guess it will turn out fine. I'll try to use it in the Climber, too.

From my memory, 25mm tubing may be a little large for a climber. But it's a cheap experiment to try it and see. With shrinkage, there's always a little leeway.
IIRC, 22mm is what I used on a Climber. I know I used 20mm on my Compact (2 layer knife) yesterday, that was quite a snug fit before shrinking, and I wouldn't recommend a thicker knife in that size.
This is the best deal I can find for the 22mm tubing. With a Prime membership 2 day shipping is free too!
http://www.amazon.com/Amico-Polyolefin-Insulation-Shrink-Tubing/dp/B008DFW7QE/ref=sr_1_4?s=industrial&ie=UTF8&qid=1375975635&sr=1-4&keywords=22mm+shrink+tubing

And ebay has a slew of diameters and colors. Be aware that the color changes (sometimes) by the size !! These are good prices, with free shipping.
http://www.ebay.com/itm/6-Feet-183cm-Heat-Shrinkable-Tube-Shrink-Many-Size-Available-/110768593129?pt=LH_DefaultDomain_0&var=&hash=item19ca5298e9

[Zed]

Lol i thought this was inner tubes  but i had a lengh of shrink wrap lying around so i did my 108mm gak and vic tinker  was pretty easy,i did do my pst but thats another story      Thanks again for posting this


Ill need wider stuff for the swisschamp

[pfrsantos]

Those 50cm cost me €3.50. I think I can make 4 cocoons for my Vics. Not expensive at all.

I'll let you know how it turned out.

 

[Schneider]

Interesting tutorial.

I think DealExtreme has some good deals on shrink tubing also.

http://dx.com/p/1m-black-heat-shrink-tubing-35mm-23467 for $3,47

and

http://dx.com/p/1m-black-heat-shrink-tubing-45mm-23468 for $3,99

for the larger sizes and they have a good selection on the smaller ones too.

If you can wait for the shipping from China that is.

[J-sews]

Good idea Neill, and thanks for the tutorial!

[kosmo]